1. Field of the Invention
The present invention relates to a method for controlling a cleaning head of an automatic cleaning device over window surfaces of a building, the cleaning head being connected to a frame which is movable in the horizontal direction (X-direction) and in the vertical direction (Z-direction) along the facade and is adapted to be positioned in front of a window surface, and the cleaning head being movable relative to the frame towards and away from the window surface to be cleaned (Y-direction) and in the two other directions (X-direction, Z-direction) perpendicular thereto.
2. Description of the Related Art
Automatic cleaning devices have already been suggested that comprise a frame which is suspended on ropes and which the cleaning head is secured to. The frame accommodates the associated units, such as water tanks, power generators, lines, etc.
The frame is suspended with ropes from a crane or a trolley which is movable along rails that are mounted on the roof of the building. The crane moves the frame from window row to window row for carrying out the cleaning operations.